A bar or slip of wood, metal, or plastic, having one or more long edges made straight within a desired degree of accuracy. It is used for testing straight lines or surfaces, drawing straight lines, and the like. Straightedges having one beveled edge may be graduated on the beveled edge. Excludes STRAIGHTEDGE, PARALLEL RULING, GUIDE CORD; SCALE (as modified); RULE (as modified) and RULER (as modified).